The present invention relates generally to ventilation systems for motor vehicles, and more particularly to a ventilation system which provides positive pressurization to the cargo area of a vehicle.
It is desirable to preserve the cleanliness of cargo carried within the cargo area of a vehicle during transport. Cargo carrying vehicles frequently travel across dusty or otherwise dirty roads. During travel, it is common for the cargo areas to ingest dust and other particulate matter, especially through cracks and openings around access doors. As it is difficult to adequately seal such cargo areas to prevent air infiltration, it is desirable to provide pressurization to the interior of the cargo area so that the interior pressure exceeds the exterior pressure, thereby preventing infiltration of contaminated exterior air.
The present invention provides a ventilation system including a duct mounted within the vehicle cab adjacent the top wall of the cab. The duct has a first end in flow communication with an opening in the forwardly facing front wall of the vehicle cab, and a second end in flow communication with the cargo area of the vehicle. The body of the duct has a low profile to maximize the interior head room of the cab. An adjustable damper is mounted within the first end of the duct across the opening in the vehicle front wall to provide control over the amount of air passing through the duct. A low profile center portion of the duct has a lower wall which inclines or slants upwardly toward the top wall of the cab with distance from the first end. Channels formed into the lower wall are arranged to collect moisture and direct the moisture downwardly toward the first end where a drain empties the duct to the exterior of the vehicle. The side walls of the low profile center portion of the duct also include a plurality of apertures with adjustable dampers to permit a portion of the air passing through the duct to communicate into the interior of the cab. The second end of the duct includes an angled portion disposed adjacent the bulkhead panel which separates the cab from the cargo area. The second angled portion slants downwardly away from the top wall with distance from the first end, and extends through an opening in the bulkhead panel into the cargo area of the vehicle. The portion extending into the cargo area forms a box-like opening. A removable filter for collecting particulate matter and moisture is situated within the duct adjacent the box-like opening to prevent these contaminants from entering the cargo area.
In one embodiment of the present invention, a fan is mounted within the duct adjacent the box-like opening. The fan directs air into the cargo area during periods of operation when the forward motion of the vehicle does not force air into the cargo area, such as when the vehicle is stopped.
In another embodiment of the invention, a power actuator is connected to the adjustable damper to provide push button air flow adjustment.
Other features of the present invention will become apparent upon consideration of the following description of exemplary embodiments and the accompanying drawings.